The invention relates to a method of mounting a magnetic head unit on a carrying arm of a movable carrier of a magnetic disk storage device for the storage and reproduction of data in digital form. The device comprises at least one rotating rigid magnetic disk, having a surface over which the magnetic head unit is moved for the storage and/or reproduction of the data in closely spaced tracks, a bearing arrangement which comprises bearing parts which are respectively connected to the movable carrier and to a stationary frame of the magnetic disk storage device, for accurately guiding the movements of the carrier relative to the frame and thereby guiding the movements of the magnetic head unit over said surface of said magnetic disk in an accurately defined plane.
Magnetic disk storage devices comprising one, two or a plurality of rigid magnetic disks, each magnetic disk serving for the storage and reproduction of data in digital form on at least one side and generally on both sides, are used on a large scale as peripheral equipment for data processing devices such as computers. The magnetic disks rotate with high speed. The magnetic heads, which are secured to the ends of the carriers, are moved over the magnetic disk surfaces to locations which are predetermined by the data processing device for thus storing data in a specific track on the magnetic disk or reproducing data from said track. The magnetic heads should be moved as rapidly as possible over the magnetic disks in order to minimize the time required for locating the correct track and storing or reproducing the data. The magnetic disks are manufactured with an extremely high degree of flatness. The magnetic heads float on a very thin film of air just above the magnetic disks. Each magnetic head is secured to a resilient magnetic head frame in order to obtain the mobility which permits the magnetic head to float on the air film and to provide a resilient load which exerts an accurately defined pressure on said head. In order to minimize the external dimensions of magnetic disk storage devices, the various manufacturers attempt to arrange the magnetic disks as closely as possible to each other. The carriers, especially when they are moved between two magnetic disks, should therefore be as flat as possible and move as close as possible to the magnetic disc surface. It is obvious that the carrying arm should never touch the magnetic disk surface because this would render the magnetic disk absolutely unserviceable. From the foregoing, it follows that movable carriers for magnetic disc storage devices should be manufactured with the necessary precision.